An Information Field Theory Approach to Regularized Inverse Problems
Speaker: Alex Albert (Purdue) Dates: 2024/11/08 Location: zoom Abstract: Inverse problems in infinite dimensions are ubiquitously encountered across the scientific disciplines. These problems are defined by the need to reconstruct continuous fields from incomplete, noisy measurements, which oftentimes leads to…
The Impact of Multiscale Dataset and a Multi-Rate Gradient Descent Approach
Speaker: Liangchen Liu (UT Austin) Dates: 2024/10/24 Location: MW 154 Abstract: Data embedded in high-dimensional spaces often follows intrinsic low-dimensional structures, but assuming a consistent scale across all directions may be too idealized. Indeed, empirical observations suggest that data distributions tend…
Frenet immersed finite element methods for interface problems: Design, analysis and future directions
Speaker: Haroun Meghaichi (OSU) Dates: 2024/08/29 Location: MW 154 Abstract: In this talk, I will go over a brief survey of unfitted methods for interface problems with an emphasis on the immersed finite element method. Next, I will describe a…
Discrete fracture models for fluid flow in fracture porous media
Speaker: Ziyao Xu (UND) Dates: 2024/04/05 Location: zoom, link Abstract: As a result of geological processes and human activities, fractures are widely distributed in subsurface rocks. Depending on the degree of precipitation, fractures can act either as highly permeable, flow-preferential…
On the Activation Function Dependence of the Spectral Bias of Neural Networks
Speaker: Qinguo Hong (Missouri S&T) Dates: 2024/03/22 Location: MW 154 Abstract: Neural networks are universal function approximators which are known to generalize well despite being dramatically overparameterized. We study this phenomenon from the point of view of the spectral bias…
A High Order Geometry Conforming Immersed Finite Element for Elliptic Interface Problems
Speaker: Haroun Meghaichi (VT) Dates: 2024/02/08 Location: zoom Abstract:We present a high order immersed finite element (IFE) method for solving the elliptic interface problem with interface-independent meshes. The IFE functions developed here satisfy the interface conditions exactly and they have…
A Model-Based Approach for Continuous-Time Policy Evaluation with Unknown Lévy Process Dynamics
Speaker: Qihao Ye (UCSD) Dates: 2024/01/26 Location: zoom Abstract: This research presents a framework for evaluating policies in a continuous-time setting, where the dynamics are unknown and represented by Lévy processes. Initially, we estimate the model using available trajectory data,…
BDDC Algorithms for Advection-diffusion problems with HDG Discretizations
Speaker: Jinjin Zhang (OSU) Dates: 2023/11/09 Location: MA 105 Abstract: In this talk, I will talk about the balancing domain decomposition by constraints (BDDC) methods for the non-symmetric positive definite system arising from the hybridizable discontinuous Galerkin (HDG) discretization of advection-diffusion…
Realizability-Preserving DG-IMEX Method for a Two-Moment Model of Special Relativistic Transport
Speaker: Joseph Hunter (OSU) Dates: 2023/11/01 Location: MA 105 Abstract: Special relativistic transport models are important for describing the transport of neutrinos, with applications to supernovae and gravitational waves. We study a two-moment model that evolves the Eulerian moments of…
Recent advances in discontinuous Galerkin discretization of Cahn–Hilliard–Navier–Stokes models for systems of two-phase flows
Speaker: Chen Liu (Purdue) Dates: 2023/10/26 Location: Zoom, link Abstract: Efficient and accurate pore-scale fluid dynamics simulators have important applications in digital rock physics. One of the popular approaches for modeling two-phase fluid flow in micro-to-millimeter pore structures is to…